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KASAN: use-after-free Read in unaccount_page_cache_page (2)

Status: premoderation: reported on 2024/08/23 02:36
Reported-by: syzbot+2660878ed6b4da17c8aa@syzkaller.appspotmail.com
First crash: 659d, last: 1d11h
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page 19 118 829d 1304d 0/2 auto-obsoleted due to no activity on 2024/05/01 01:14
android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page (3) 19 133 2d15h 529d 0/2 premoderation: reported on 2024/12/31 14:15
android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page 19 150 783d 1311d 0/2 auto-obsoleted due to no activity on 2024/06/10 16:28
android-54 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page 19 2 864d 945d 0/2 auto-obsoleted due to no activity on 2024/04/30 10:15
android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page (2) 19 1 669d 669d 0/2 auto-obsoleted due to no activity on 2024/11/11 21:33
android-54 KASAN: use-after-free Read in unaccount_page_cache_page 19 143 1095d 1309d 0/2 auto-obsoleted due to no activity on 2023/08/23 09:09
android-54 KASAN: use-after-free Read in unaccount_page_cache_page (2) 19 5 387d 412d 0/2 auto-obsoleted due to no activity on 2025/08/20 03:09

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in cleancache_fs_enabled_mapping include/linux/cleancache.h:56 [inline]
BUG: KASAN: use-after-free in cleancache_invalidate_page include/linux/cleancache.h:110 [inline]
BUG: KASAN: use-after-free in unaccount_page_cache_page+0x6f2/0x760 mm/filemap.c:172
Read of size 4 at addr ffff88810e1de470 by task kswapd0/46

CPU: 0 PID: 46 Comm: kswapd0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0xf1/0x140 mm/kasan/report.c:444
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
 cleancache_fs_enabled_mapping include/linux/cleancache.h:56 [inline]
 cleancache_invalidate_page include/linux/cleancache.h:110 [inline]
 unaccount_page_cache_page+0x6f2/0x760 mm/filemap.c:172
 __delete_from_page_cache+0xbe/0x470 mm/filemap.c:240
 __remove_mapping+0x80a/0x980 mm/vmscan.c:1216
 shrink_page_list+0x24c4/0x5af0 mm/vmscan.c:1829
 shrink_inactive_list mm/vmscan.c:2338 [inline]
 shrink_list mm/vmscan.c:2583 [inline]
 shrink_lruvec+0x1209/0x39a0 mm/vmscan.c:5800
 shrink_node_memcgs mm/vmscan.c:5992 [inline]
 shrink_node+0x1205/0x2aa0 mm/vmscan.c:6022
 kswapd_shrink_node mm/vmscan.c:6773 [inline]
 balance_pgdat+0x1000/0x21f0 mm/vmscan.c:6963
 kswapd+0x65b/0xcd0 mm/vmscan.c:7222
 kthread+0x411/0x500 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Allocated by task 4500:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:433 [inline]
 __kasan_slab_alloc+0xbd/0xf0 mm/kasan/common.c:466
 kasan_slab_alloc include/linux/kasan.h:217 [inline]
 slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550
 slab_alloc_node mm/slub.c:3245 [inline]
 slab_alloc mm/slub.c:3255 [inline]
 kmem_cache_alloc+0xf7/0x260 mm/slub.c:3260
 getname_flags+0xb9/0x500 fs/namei.c:138
 getname+0x19/0x20 fs/namei.c:217
 do_sys_openat2+0xeb/0x7f0 fs/open.c:1230
 do_sys_open fs/open.c:1252 [inline]
 __do_sys_openat fs/open.c:1268 [inline]
 __se_sys_openat fs/open.c:1263 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1263
 x64_sys_call+0x219/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 4500:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373
 kasan_slab_free include/linux/kasan.h:193 [inline]
 slab_free_hook mm/slub.c:1728 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1754
 slab_free mm/slub.c:3526 [inline]
 kmem_cache_free+0x100/0x320 mm/slub.c:3544
 putname+0x111/0x160 fs/namei.c:271
 do_sys_openat2+0x6df/0x7f0 fs/open.c:1245
 do_sys_open fs/open.c:1252 [inline]
 __do_sys_openat fs/open.c:1268 [inline]
 __se_sys_openat fs/open.c:1263 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1263
 x64_sys_call+0x219/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88810e1dd500
 which belongs to the cache names_cache of size 4096
The buggy address is located 3952 bytes inside of
 4096-byte region [ffff88810e1dd500, ffff88810e1de500)
The buggy address belongs to the page:
page:ffffea0004387600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10e1d8
head:ffffea0004387600 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 dead000000000122 ffff8881001c5200
raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4500, ts 193855320245, free_ts 184285406913
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611
 get_page_from_freelist+0x2d3a/0x2dc0 mm/page_alloc.c:4485
 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5822
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1937 [inline]
 new_slab+0xa1/0x4d0 mm/slub.c:2000
 ___slab_alloc+0x381/0x810 mm/slub.c:3033
 __slab_alloc+0x49/0x90 mm/slub.c:3120
 slab_alloc_node mm/slub.c:3211 [inline]
 slab_alloc mm/slub.c:3255 [inline]
 kmem_cache_alloc+0x138/0x260 mm/slub.c:3260
 getname_flags+0xb9/0x500 fs/namei.c:138
 getname+0x19/0x20 fs/namei.c:217
 do_sys_openat2+0xeb/0x7f0 fs/open.c:1230
 do_sys_open fs/open.c:1252 [inline]
 __do_sys_openat fs/open.c:1268 [inline]
 __se_sys_openat fs/open.c:1263 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1263
 x64_sys_call+0x219/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1472 [inline]
 free_pcp_prepare mm/page_alloc.c:1544 [inline]
 free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534
 free_unref_page+0xae/0x540 mm/page_alloc.c:3616
 free_the_page mm/page_alloc.c:805 [inline]
 __free_pages+0x6c/0x100 mm/page_alloc.c:5898
 __free_slab+0xe8/0x1e0 mm/slub.c:2025
 free_slab mm/slub.c:2040 [inline]
 discard_slab mm/slub.c:2046 [inline]
 __unfreeze_partials+0x160/0x190 mm/slub.c:2532
 put_cpu_partial+0xc6/0x120 mm/slub.c:2612
 __slab_free+0x1d4/0x290 mm/slub.c:3395
 do_slab_free mm/slub.c:3514 [inline]
 ___cache_free+0x104/0x120 mm/slub.c:3535
 qlink_free+0x4d/0x90 mm/kasan/quarantine.c:157
 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xf0 mm/kasan/common.c:443
 kasan_slab_alloc include/linux/kasan.h:217 [inline]
 slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550
 slab_alloc_node mm/slub.c:3245 [inline]
 slab_alloc mm/slub.c:3255 [inline]
 kmem_cache_alloc+0xf7/0x260 mm/slub.c:3260
 kmem_cache_alloc_node include/linux/slab.h:492 [inline]
 __alloc_skb+0xe0/0x740 net/core/skbuff.c:416
 alloc_skb include/linux/skbuff.h:1183 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 rtmsg_ifa+0xfa/0x1d0 net/ipv4/devinet.c:1927

Memory state around the buggy address:
 ffff88810e1de300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88810e1de380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88810e1de400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff88810e1de480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88810e1de500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (191):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/12 09:49 android13-5.15-lts 30f5554a846e e93da63e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/06/06 03:15 android13-5.15-lts 8969ee93a483 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/05/31 12:23 android13-5.15-lts 8969ee93a483 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/05/24 19:05 android13-5.15-lts 05eea940894a c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/05/08 17:13 android13-5.15-lts fbdcb39071da b2988c17 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/05/07 03:29 android13-5.15-lts a5c2f59daca2 f250db59 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/05/06 18:44 android13-5.15-lts a5c2f59daca2 1dddfd3d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/05/06 03:09 android13-5.15-lts e63ebedc51b2 26da2c66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/05/04 04:28 android13-5.15-lts e63ebedc51b2 a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/05/04 01:55 android13-5.15-lts e63ebedc51b2 a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/05/03 10:10 android13-5.15-lts e63ebedc51b2 a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/04/29 06:01 android13-5.15-lts e63ebedc51b2 95008c03 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/04/14 05:00 android13-5.15-lts 7fad219d720d 1a086e7c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/04/12 15:10 android13-5.15-lts 7fad219d720d 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/04/12 05:59 android13-5.15-lts 7fad219d720d 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/04/10 19:50 android13-5.15-lts 7fad219d720d 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/03/28 07:40 android13-5.15-lts 7fad219d720d 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/03/22 03:21 android13-5.15-lts 60dba25bf158 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/03/21 01:26 android13-5.15-lts 60dba25bf158 ac6f1dff .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/03/11 22:22 android13-5.15-lts 60dba25bf158 2d88ab01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/03/05 22:17 android13-5.15-lts e714749f59d3 d20b04c8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/28 19:02 android13-5.15-lts e714749f59d3 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/28 07:48 android13-5.15-lts e714749f59d3 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/24 15:06 android13-5.15-lts 13d6d33696ef 96b1aa46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/22 15:39 android13-5.15-lts 13d6d33696ef 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/18 08:34 android13-5.15-lts 13d6d33696ef 39751c21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/15 23:12 android13-5.15-lts 13d6d33696ef 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/14 17:19 android13-5.15-lts 13d6d33696ef 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/12 12:41 android13-5.15-lts c3393955a6be 76a109e2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/11 10:07 android13-5.15-lts c3393955a6be 441e25b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/04 12:39 android13-5.15-lts 7e1070528954 42b01fab .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/02 02:56 android13-5.15-lts 7e1070528954 6b8752f2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/01 20:04 android13-5.15-lts 7e1070528954 6b8752f2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/02/01 06:23 android13-5.15-lts 7e1070528954 6b8752f2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/01/30 06:35 android13-5.15-lts 7e1070528954 bfa73b7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/01/27 20:24 android13-5.15-lts 7e1070528954 9a514c2f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/01/26 07:21 android13-5.15-lts 00b50d06692d 55756628 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2026/06/06 12:35 android13-5.15-lts 8969ee93a483 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2026/05/03 22:22 android13-5.15-lts e63ebedc51b2 a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2026/04/30 22:26 android13-5.15-lts e63ebedc51b2 a7464baf .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2026/03/06 11:59 android13-5.15-lts e714749f59d3 31e9c887 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2026/02/15 01:58 android13-5.15-lts 13d6d33696ef 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2026/02/03 06:38 android13-5.15-lts 7e1070528954 d78927dd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2026/01/30 07:41 android13-5.15-lts 7e1070528954 bfa73b7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
* Struck through repros no longer work on HEAD.